The invention relates to an electrodynamic actuator for an optical write-in or read-out unit which is aligned with respect to signal tracks of a storage medium in order to direct a focused light beam onto a work position.
Electrodynamic actuators of this type are known from audio, video and data systems technology. A focused light beam is guided by an optical system onto a storage medium, which can be, for example, a rotating plate (German patent documents Offenlegungsschrift 2,810,616). It is true that in this German Offenlegungsschrift only read-out takes place with the aid of the beam bundle; however write-in is equally possible, as is known from German Offenlegungsschrift 1,613,987. Both with write-in and also with read-out, it is necessary first to bring the laser beam into the write-in or read-out work position by means of an electromechanical control device, and then in this position to focus the objective by means of an actuator onto the precise position to be written in or read out.
From German Patent 3,234,288 an electrodynamic actuator is known in which the optical system is mounted floating in a magnet system. Furthermore, an actuator with movable coils is known from European patent documents EP-A-144,445. The coils have flexible supply leads. The flexible supply leads are expensive, and are likely to interfere with the movements of the actuator.